Load Specifications
Load data in caliber 7.5 x 55 Swiss with .308 | 165gr | Swift Scirocco bullet and 93 powders. The key underlying parameters are shown in the table above. The recommended powders for this cartridge and bullet combination are Alliant Power Pro 2000-MR, ReloadSwiss RS 60 and Alliant Reloder-17.
Important Notice: DO NOT go below Minimum Charge or above Maximum Charge. Since we have no control over the equipment and components used, any responsibility and liability for the results achieved is rejected.
Only powders/loads that match the current filter criteria are displayed: max pressure of a load ≤ 90% of max. standardized pressure, fill rate ≥ 80% and propellant combustion ≥ 95%. Use the sliders above the tables to adjust these thresholds.
Charge: Powder weight in grains. Start with the minimum load and work up carefully.
FR (Fill Rate): Case fill as a percentage. Values above 100% mean compressed loads.
MaxP / %: Maximum chamber pressure in bar and as a percentage of the standardized maximum for this caliber.
V(0): Muzzle velocity in feet per second (fps) at the standardized barrel length.
z (Powder Burn): Estimated propellant combustion percentage at bullet exit.
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You can find more information in our FAQ: How can I use the Personalized Load Calculator?
Max Load - Barrel Length: 31"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 84% | 47,427 psi | 86% | 2674 fps | 100% |
| Accurate 2460 | <<locked>> | 82% | 48,501 psi | 88% | 2736 fps | 100% |
| Accurate 2495 | <<locked>> | 90% | 47,543 psi | 86% | 2733 fps | 100% |
| Accurate 2520 | <<locked>> | 86% | 49,632 psi | 90% | 2795 fps | 100% |
| Accurate 4064 | <<locked>> | 92% | 47,456 psi | 86% | 2776 fps | 100% |
| Accurate 4350ᴾ | <<locked>> | 100% | 45,890 psi | 83% | 2835 fps | 98.8% |
| ADI AR 2206H | <<locked>> | 88% | 49,400 psi | 90% | 2812 fps | 99.7% |
| ADI AR 2208 | <<locked>> | 92% | 47,152 psi | 86% | 2756 fps | 99.1% |
| ADI Benchmark 8208 | <<locked>> | 86% | 48,820 psi | 89% | 2766 fps | 100% |
| Alliant AR-Comp | <<locked>> | 86% | 48,080 psi | 87% | 2743 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 82% | 49,821 psi | 90% | 2864 fps | 99.9% |
| Alliant Power Pro 2000-MR | <<locked>> | 90% | 48,283 psi | 88% | 2913 fps | 99.4% |
| Alliant Reloder- TS 15.5 | <<locked>> | 94% | 49,516 psi | 90% | 2828 fps | 100% |
| Alliant Reloder-15 | <<locked>> | 90% | 47,137 psi | 86% | 2799 fps | 99.3% |
| Alliant Reloder-16ᴾ | <<locked>> | 100% | 45,948 psi | 83% | 2844 fps | 98.9% |
| Alliant Reloder-17 | <<locked>> | 98% | 49,429 psi | 90% | 2936 fps | 100% |
| Alliant Reloder-23ᴾ | <<locked>> | 100% | 32,401 psi | 59% | 2579 fps | 96.9% |
| Baschieri & Pellagri 107 | <<locked>> | 88% | 48,631 psi | 88% | 2818 fps | 99.1% |
| Bofors RP3 | <<locked>> | 94% | 49,530 psi | 90% | 2841 fps | 100% |
| Bofors RP7 | <<locked>> | 96% | 47,659 psi | 86% | 2749 fps | 95.7% |
| Hodgdon Benchmark | <<locked>> | 84% | 47,964 psi | 87% | 2707 fps | 100% |
| Hodgdon BL-C2 | <<locked>> | 86% | 47,050 psi | 85% | 2792 fps | 100% |
| Hodgdon CFE223 | <<locked>> | 84% | 48,457 psi | 88% | 2881 fps | 99.5% |
| Hodgdon H322 | <<locked>> | 82% | 49,240 psi | 89% | 2762 fps | 100% |
| Hodgdon H380 | <<locked>> | 92% | 47,572 psi | 86% | 2795 fps | 98.5% |
| Hodgdon H414ᴾ | <<locked>> | 100% | 49,458 psi | 90% | 2884 fps | 97% |
| Hodgdon H4895 | <<locked>> | 88% | 49,777 psi | 90% | 2822 fps | 99.9% |
| Hodgdon Hybrid 100Vᴾ | <<locked>> | 100% | 41,901 psi | 76% | 2720 fps | 99.2% |
| Hodgdon LEVERevolution | <<locked>> | 90% | 47,950 psi | 87% | 2844 fps | 100% |
| Hodgdon TrailBossᴾ | <<locked>> | 100% | 34,621 psi | 63% | 1703 fps | 100% |
| Hodgdon VARGET | <<locked>> | 88% | 47,834 psi | 87% | 2772 fps | 99.8% |
| IMR 3031 | <<locked>> | 88% | 48,950 psi | 89% | 2805 fps | 100% |
| IMR 4064 | <<locked>> | 92% | 49,603 psi | 90% | 2785 fps | 99.5% |
| IMR 4166 Enduron | <<locked>> | 88% | 47,340 psi | 86% | 2713 fps | 96.2% |
| IMR 4451 Enduron | <<locked>> | 96% | 49,588 psi | 90% | 2785 fps | 96.7% |
| IMR 4831ᴾ | <<locked>> | 100% | 44,005 psi | 80% | 2779 fps | 98.5% |
| IMR 4895 | <<locked>> | 90% | 48,269 psi | 88% | 2828 fps | 99.7% |
| IMR 8208 XBR | <<locked>> | 86% | 48,820 psi | 89% | 2766 fps | 100% |
| Lovex D073.5 | <<locked>> | 82% | 48,428 psi | 88% | 2746 fps | 100% |
| Lovex D073.6 | <<locked>> | 88% | 47,921 psi | 87% | 2782 fps | 100% |
| Lovex S060 | <<locked>> | 86% | 46,978 psi | 85% | 2694 fps | 99.5% |
| Lovex S062 | <<locked>> | 92% | 49,081 psi | 89% | 2785 fps | 100% |
| Lovex S065 | <<locked>> | 98% | 48,298 psi | 88% | 2776 fps | 97.9% |
| Lovex S070ᴾ | <<locked>> | 100% | 48,762 psi | 88% | 2805 fps | 97% |
| Norma 201 | <<locked>> | 88% | 48,254 psi | 88% | 2759 fps | 100% |
| Norma 202 | <<locked>> | 88% | 48,312 psi | 88% | 2762 fps | 100% |
| Norma 203B | <<locked>> | 92% | 49,298 psi | 89% | 2835 fps | 99.7% |
| Norma URPᴾ | <<locked>> | 100% | 46,093 psi | 84% | 2831 fps | 98.7% |
| Ramshot Big Game | <<locked>> | 92% | 49,385 psi | 90% | 2858 fps | 99.7% |
| Ramshot Hunterᴾ | <<locked>> | 100% | 45,469 psi | 83% | 2822 fps | 97% |
| Ramshot TAC | <<locked>> | 86% | 48,994 psi | 89% | 2776 fps | 98.1% |
| Ramshot Wild Boar | <<locked>> | 86% | 48,109 psi | 87% | 2799 fps | 99.6% |
| Ramshot X-Terminator | <<locked>> | 84% | 49,632 psi | 90% | 2762 fps | 99.6% |
| ReloadSwiss RS 14ᴾ | <<locked>> | 100% | 35,143 psi | 64% | 1745 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 82% | 48,225 psi | 88% | 2746 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 92% | 48,385 psi | 88% | 2776 fps | 97.2% |
| ReloadSwiss RS 52 | <<locked>> | 90% | 49,603 psi | 90% | 2907 fps | 99.6% |
| ReloadSwiss RS 60 | <<locked>> | 96% | 49,603 psi | 90% | 2943 fps | 100% |
| ReloadSwiss RS 62ᴾ | <<locked>> | 100% | 45,832 psi | 83% | 2858 fps | 98.5% |
| ReloadSwiss RS 70ᴾ | <<locked>> | 100% | 46,833 psi | 85% | 2877 fps | 98.1% |
| Rottweil R 901 | <<locked>> | 86% | 49,617 psi | 90% | 2746 fps | 100% |
| Rottweil R 902 | <<locked>> | 90% | 48,501 psi | 88% | 2753 fps | 100% |
| Rottweil R 903 | <<locked>> | 96% | 49,052 psi | 89% | 2825 fps | 99.9% |
| Rottweil R 907 | <<locked>> | 96% | 47,659 psi | 86% | 2749 fps | 95.7% |
| Shooters World Long Rifle | <<locked>> | 98% | 48,298 psi | 88% | 2776 fps | 97.9% |
| Shooters World Match Rifle | <<locked>> | 88% | 47,921 psi | 87% | 2782 fps | 100% |
| Shooters World Precision | <<locked>> | 92% | 49,081 psi | 89% | 2785 fps | 100% |
| Shooters World SW4350ᴾ | <<locked>> | 100% | 48,762 psi | 88% | 2805 fps | 97% |
| SNPE Vectan SP 11 | <<locked>> | 94% | 47,718 psi | 87% | 2838 fps | 99.6% |
| SNPE Vectan SP 7 | <<locked>> | 86% | 46,978 psi | 85% | 2749 fps | 98.2% |
| SNPE Vectan SP 9 | <<locked>> | 88% | 47,572 psi | 86% | 2779 fps | 99.6% |
| SNPE Vectan Tubal 3000 | <<locked>> | 86% | 47,384 psi | 86% | 2657 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 94% | 49,676 psi | 90% | 2697 fps | 100% |
| SNPE Vectan Tubal 7000 | <<locked>> | 98% | 48,356 psi | 88% | 2726 fps | 96.5% |
| Somchem S321 | <<locked>> | 84% | 49,472 psi | 90% | 2799 fps | 100% |
| Somchem S335 | <<locked>> | 88% | 49,414 psi | 90% | 2700 fps | 100% |
| Somchem S341 | <<locked>> | 88% | 49,676 psi | 90% | 2795 fps | 99.7% |
| Somchem S355 | <<locked>> | 94% | 47,036 psi | 85% | 2782 fps | 99.7% |
| Somchem S365ᴾ | <<locked>> | 100% | 40,857 psi | 74% | 2779 fps | 99.9% |
| Vihtavuori N130 | <<locked>> | 82% | 47,224 psi | 86% | 2628 fps | 100% |
| Vihtavuori N133 | <<locked>> | 86% | 47,413 psi | 86% | 2648 fps | 100% |
| Vihtavuori N135 | <<locked>> | 90% | 47,616 psi | 86% | 2723 fps | 100% |
| Vihtavuori N140 | <<locked>> | 90% | 48,892 psi | 89% | 2740 fps | 100% |
| Vihtavuori N150 | <<locked>> | 96% | 48,051 psi | 87% | 2759 fps | 100% |
| Vihtavuori N160ᴾ | <<locked>> | 100% | 48,457 psi | 88% | 2822 fps | 98.9% |
| Vihtavuori N530 | <<locked>> | 86% | 48,878 psi | 89% | 2759 fps | 100% |
| Vihtavuori N540 | <<locked>> | 90% | 47,152 psi | 86% | 2740 fps | 100% |
| Vihtavuori N550ᴾ | <<locked>> | 100% | 47,427 psi | 86% | 2831 fps | 98.7% |
| Vihtavuori N555ᴾ | <<locked>> | 100% | 34,069 psi | 62% | 2651 fps | 96.8% |
| Winchester 6.5 StaBALLᴾ | <<locked>> | 100% | 49,705 psi | 90% | 2808 fps | 99.9% |
| Winchester 748 | <<locked>> | 86% | 47,979 psi | 87% | 2808 fps | 100% |
| Winchester 760ᴾ | <<locked>> | 100% | 49,763 psi | 90% | 2887 fps | 97.1% |
| Winchester StaBALL Match | <<locked>> | 88% | 47,050 psi | 85% | 2785 fps | 99.8% |
Recommended = one of the top powders for this cartridge and bullet combination.
Start Load - Barrel Length: 31"
| Powder | Charge | FR | MaxP | % | V(0) | z |
|---|---|---|---|---|---|---|
| Accurate 2015 | <<locked>> | 80% | 41,771 psi | 76% | 2585 fps | 100% |
| Accurate 2460 | <<locked>> | 80% | 45,281 psi | 82% | 2687 fps | 100% |
| Accurate 2495 | <<locked>> | 80% | 34,287 psi | 62% | 2507 fps | 100% |
| Accurate 2520 | <<locked>> | 80% | 40,524 psi | 74% | 2648 fps | 100% |
| Accurate 4064 | <<locked>> | 80% | 32,445 psi | 59% | 2497 fps | 99.8% |
| Accurate 4350 | <<locked>> | 90% | 32,401 psi | 59% | 2566 fps | 95.5% |
| ADI AR 2206H | <<locked>> | 80% | 38,392 psi | 70% | 2608 fps | 98.2% |
| ADI AR 2208 | <<locked>> | 80% | 32,721 psi | 59% | 2461 fps | 95.9% |
| ADI Benchmark 8208 | <<locked>> | 80% | 40,364 psi | 73% | 2618 fps | 99.4% |
| Alliant AR-Comp | <<locked>> | 80% | 39,523 psi | 72% | 2612 fps | 100% |
| Alliant Power Pro 1200-R | <<locked>> | 80% | 46,717 psi | 85% | 2812 fps | 99.8% |
| Alliant Power Pro 2000-MR | 43.6 gr | 80% | 34,606 psi | 63% | 2621 fps | 96.1% |
| Alliant Reloder- TS 15.5 | <<locked>> | 80% | 31,662 psi | 57% | 2480 fps | 97.4% |
| Alliant Reloder-15 | <<locked>> | 80% | 34,330 psi | 62% | 2539 fps | 96.7% |
| Alliant Reloder-16 | <<locked>> | 90% | 33,953 psi | 62% | 2582 fps | 95.6% |
| Alliant Reloder-17 | 44 gr | 82% | 29,428 psi | 53% | 2493 fps | 95.7% |
| Alliant Reloder-23 | <<locked>> | 96% | 28,776 psi | 52% | 2474 fps | 95.1% |
| Baschieri & Pellagri 107 | <<locked>> | 80% | 37,188 psi | 67% | 2605 fps | 96.9% |
| Bofors RP3 | <<locked>> | 80% | 30,937 psi | 56% | 2477 fps | 97.4% |
| Bofors RP7 | <<locked>> | 94% | 44,773 psi | 81% | 2700 fps | 95% |
| Hodgdon Benchmark | <<locked>> | 80% | 42,540 psi | 77% | 2612 fps | 99.8% |
| Hodgdon BL-C2 | <<locked>> | 80% | 38,580 psi | 70% | 2638 fps | 99.5% |
| Hodgdon CFE223 | <<locked>> | 80% | 42,235 psi | 77% | 2769 fps | 98.7% |
| Hodgdon H322 | <<locked>> | 80% | 45,876 psi | 83% | 2710 fps | 100% |
| Hodgdon H380 | <<locked>> | 82% | 34,301 psi | 62% | 2533 fps | 95.3% |
| Hodgdon H414 | <<locked>> | 96% | 43,453 psi | 79% | 2776 fps | 95.6% |
| Hodgdon H4895 | <<locked>> | 80% | 38,667 psi | 70% | 2618 fps | 98.7% |
| Hodgdon Hybrid 100V | <<locked>> | 88% | 29,022 psi | 53% | 2425 fps | 95.6% |
| Hodgdon LEVERevolution | <<locked>> | 80% | 34,490 psi | 63% | 2582 fps | 98.3% |
| Hodgdon TrailBoss | <<locked>> | 80% | 25,817 psi | 47% | 1522 fps | 100% |
| Hodgdon VARGET | <<locked>> | 80% | 37,318 psi | 68% | 2575 fps | 98.4% |
| IMR 3031 | <<locked>> | 80% | 37,521 psi | 68% | 2618 fps | 100% |
| IMR 4064 | <<locked>> | 80% | 34,272 psi | 62% | 2490 fps | 96.7% |
| IMR 4166 Enduron | <<locked>> | 86% | 44,556 psi | 81% | 2661 fps | 95.5% |
| IMR 4451 Enduron | <<locked>> | 92% | 43,961 psi | 80% | 2687 fps | 95.3% |
| IMR 4831 | <<locked>> | 90% | 31,836 psi | 58% | 2523 fps | 95.2% |
| IMR 4895 | <<locked>> | 80% | 35,099 psi | 64% | 2572 fps | 97.6% |
| IMR 8208 XBR | <<locked>> | 80% | 40,364 psi | 73% | 2618 fps | 99.4% |
| Lovex D073.5 | <<locked>> | 80% | 45,252 psi | 82% | 2697 fps | 100% |
| Lovex D073.6 | <<locked>> | 80% | 36,608 psi | 66% | 2582 fps | 99.8% |
| Lovex S060 | <<locked>> | 80% | 39,175 psi | 71% | 2549 fps | 98.3% |
| Lovex S062 | <<locked>> | 80% | 34,011 psi | 62% | 2500 fps | 98.4% |
| Lovex S065 | <<locked>> | 90% | 37,884 psi | 69% | 2582 fps | 95.4% |
| Lovex S070 | <<locked>> | 96% | 42,888 psi | 78% | 2700 fps | 95.6% |
| Norma 201 | <<locked>> | 80% | 37,623 psi | 68% | 2562 fps | 99% |
| Norma 202 | <<locked>> | 80% | 37,608 psi | 68% | 2575 fps | 100% |
| Norma 203B | <<locked>> | 80% | 33,707 psi | 61% | 2530 fps | 97.1% |
| Norma URP | <<locked>> | 90% | 33,547 psi | 61% | 2572 fps | 95.5% |
| Ramshot Big Game | <<locked>> | 80% | 33,199 psi | 60% | 2536 fps | 96.7% |
| Ramshot Hunter | <<locked>> | 96% | 40,074 psi | 73% | 2713 fps | 95.5% |
| Ramshot TAC | <<locked>> | 80% | 40,306 psi | 73% | 2615 fps | 96.2% |
| Ramshot Wild Boar | <<locked>> | 80% | 39,334 psi | 71% | 2638 fps | 98.4% |
| Ramshot X-Terminator | <<locked>> | 80% | 43,584 psi | 79% | 2661 fps | 99% |
| ReloadSwiss RS 14 | <<locked>> | 80% | 25,875 psi | 47% | 1558 fps | 100% |
| ReloadSwiss RS 40 | <<locked>> | 80% | 45,324 psi | 82% | 2700 fps | 100% |
| ReloadSwiss RS 50 | <<locked>> | 86% | 39,827 psi | 72% | 2618 fps | 95.1% |
| ReloadSwiss RS 52 | <<locked>> | 80% | 35,215 psi | 64% | 2628 fps | 97% |
| ReloadSwiss RS 60 | 42.9 gr | 80% | 29,341 psi | 53% | 2503 fps | 98.2% |
| ReloadSwiss RS 62 | <<locked>> | 92% | 35,041 psi | 64% | 2638 fps | 95.8% |
| ReloadSwiss RS 70 | <<locked>> | 94% | 38,493 psi | 70% | 2703 fps | 95.8% |
| Rottweil R 901 | <<locked>> | 80% | 41,292 psi | 75% | 2605 fps | 100% |
| Rottweil R 902 | <<locked>> | 80% | 35,752 psi | 65% | 2513 fps | 98.7% |
| Rottweil R 903 | <<locked>> | 80% | 29,095 psi | 53% | 2421 fps | 96.3% |
| Rottweil R 907 | <<locked>> | 94% | 44,773 psi | 81% | 2700 fps | 95% |
| Shooters World Long Rifle | <<locked>> | 90% | 37,884 psi | 69% | 2582 fps | 95.4% |
| Shooters World Match Rifle | <<locked>> | 80% | 36,608 psi | 66% | 2582 fps | 99.8% |
| Shooters World Precision | <<locked>> | 80% | 34,011 psi | 62% | 2500 fps | 98.4% |
| Shooters World SW4350 | <<locked>> | 96% | 42,888 psi | 78% | 2700 fps | 95.6% |
| SNPE Vectan SP 11 | <<locked>> | 80% | 30,400 psi | 55% | 2470 fps | 95.7% |
| SNPE Vectan SP 7 | <<locked>> | 80% | 38,290 psi | 69% | 2585 fps | 96.3% |
| SNPE Vectan SP 9 | <<locked>> | 80% | 36,840 psi | 67% | 2575 fps | 97.9% |
| SNPE Vectan Tubal 3000 | <<locked>> | 80% | 39,378 psi | 71% | 2523 fps | 100% |
| SNPE Vectan Tubal 5000 | <<locked>> | 80% | 32,329 psi | 59% | 2395 fps | 99.9% |
| SNPE Vectan Tubal 7000 | <<locked>> | 94% | 42,090 psi | 76% | 2621 fps | 95.1% |
| Somchem S321 | <<locked>> | 80% | 43,221 psi | 78% | 2694 fps | 99.8% |
| Somchem S335 | <<locked>> | 80% | 38,798 psi | 70% | 2526 fps | 100% |
| Somchem S341 | <<locked>> | 80% | 37,869 psi | 69% | 2585 fps | 98% |
| Somchem S355 | <<locked>> | 80% | 30,313 psi | 55% | 2434 fps | 96.5% |
| Somchem S365 | <<locked>> | 84% | 24,860 psi | 45% | 2362 fps | 95.1% |
| Vihtavuori N130 | <<locked>> | 80% | 44,628 psi | 81% | 2589 fps | 100% |
| Vihtavuori N133 | <<locked>> | 80% | 39,494 psi | 72% | 2520 fps | 100% |
| Vihtavuori N135 | <<locked>> | 80% | 34,751 psi | 63% | 2507 fps | 100% |
| Vihtavuori N140 | <<locked>> | 80% | 35,491 psi | 64% | 2510 fps | 99.9% |
| Vihtavuori N150 | <<locked>> | 80% | 28,616 psi | 52% | 2372 fps | 97.3% |
| Vihtavuori N160 | <<locked>> | 88% | 33,083 psi | 60% | 2520 fps | 95.1% |
| Vihtavuori N530 | <<locked>> | 80% | 40,161 psi | 73% | 2612 fps | 99.4% |
| Vihtavuori N540 | <<locked>> | 80% | 34,243 psi | 62% | 2503 fps | 99.7% |
| Vihtavuori N550 | <<locked>> | 90% | 34,374 psi | 62% | 2575 fps | 95.6% |
| Vihtavuori N555 | <<locked>> | 96% | 30,095 psi | 55% | 2546 fps | 95.2% |
| Winchester 6.5 StaBALL | <<locked>> | 84% | 29,530 psi | 54% | 2398 fps | 95.8% |
| Winchester 748 | <<locked>> | 80% | 39,175 psi | 71% | 2654 fps | 99.7% |
| Winchester 760 | <<locked>> | 96% | 43,714 psi | 79% | 2779 fps | 95.7% |
| Winchester StaBALL Match | <<locked>> | 80% | 36,013 psi | 65% | 2575 fps | 98.3% |
Recommended = one of the top powders for this cartridge and bullet combination.
ᴾ possible press load - work up slowly to this load while watching for signs of excessive pressure.
This overview compares 108 powders for 7.5 x 55 Swiss loaded with the .308 | 165gr | Swift Scirocco. ReloadSwiss RS 60 delivers the highest muzzle velocity at 2,943 fps; across all powders the maximum-charge window runs from 1,703 fps to 2,943 fps. Accurate 3100 gives the best case fill at 100 %, and 108 of the 108 powders fall inside the usable 80–100 % fill window.
Relative to the caliber's maximum pressure (380 MPa), the top charges use 52–90 %, leaving at least 10 % headroom. The 165.0 gr projectile in 0.308" calls for a 1:11.5 twist; slower twists will usually not stabilise this weight. Accurate 3100, Accurate 4350, ADI AR 2209 reach 100 % fill or more at maximum charge, so these are compressed loads: they need a long drop tube to seat cleanly and react sensitively to the case capacity of your own brass lot. Alliant Power Pro 2000-MR, ReloadSwiss RS 60, Alliant Reloder-17 rank at the top here: for 7.5 x 55 Swiss with the .308 | 165gr | Swift Scirocco they combine a high case fill with complete burn and sit in the upper velocity band. As outliers, Accurate 3100, ADI AR 2209, Alliant Reloder-19 burn incompletely and react more sensitively to barrel length and temperature. Always begin at the start load and work up in small increments while checking case and primer for pressure signs.